Dynamical instability of the González-Díaz black hole model

The black hole model constructed by Gonzalez-Diaz, with de Sitter metric inside the horizon and Schwarzschild metric outside it, is investigated by considering a spherical region with false vacuum surrounded by ordinary vacuum. The hypersurface between the two different vacuum regions is a spherical singular layer. A static solution of the equation of motion of the junction surface exists in the limit that the “horizon positions” of the de Sitter and Schwarzschild regions approach each other. This corresponds to the Gonzalez-Diaz model. A stability analysis shows that this black hole model is dynamically unstable.